at the 2010 u.s. open. [ more screaming ] >> 3,000 competitors from 40 countries were at the karate karate tournament. she credits her success to hard work -- [ continuing screaming ] >> -- and a vicious yell. she says she trains every day before a big tournament. the division she competes in is 7 to 10-year-old boys and girls. >> wouldn't you like her to be your friend on the playground? >> i wouldn't want to be her enemy. >>> facebook has signed up their 500 millionth member. they get new customers every eight seconds and the users average 130 friends each. our question. day: who is the most interesting person you have reconnected with on facebook? >> david from clayton on facebook says, my high school teachers and college professors. i see these ladies and gentlemen in a whole new light at the age of 47. [ laughter ] >> a lot smarter, huh? "i have reconnected with some of my bestest of friends that have always been in my mind. i have really enjoyed getting to be part of their lives once again." >> raymond says, "many people from the past, from grade school to now, most from high school.